Cannot maitain dir structure when zipping files

Dear Ranchers, I need help with java zip utility, My below code snippet is not able to maintain the Dir
structure, i.e it zips all the files into a single out Dir, also it starts zipping the all the Dir on the absolute path
of the input e.g if input is C:\\dir1\dir2\dir3 i want it to zip only files in dir3 and its sub directories. HELP !!